07 September 2011

Oracle ASM provides near unlimited capacity for future growth, but does have some storage limits. For example, Oracle ASM has the following limits on the number of disk groups, disks, and files:

63 disk groups in a storage system

10,000 Oracle ASM disks in a storage system

1 million files for each disk group

Without any Oracle Exadata Storage, Oracle ASM has these storage limits:

2 terabytes (TB) maximum storage for each Oracle ASM disk

20 petabytes (PB) maximum for the storage system

With all Oracle Exadata Storage, Oracle ASM has these storage limits:

4 PB maximum storage for each Oracle ASM disk

40 exabytes (EB) maximum for the storage system

The maximum size limit of a disk group equals the maximum disk size multiplied by the maximum number of disks in a disk group (10,000).

File size limits are dependent on the value of the disk group compatibility attributes. Oracle ASM supports file sizes greater than 128 TB in any redundancy mode when the COMPATIBLE.RDBMS disk group attribute is set greater than10.1.

If COMPATIBLE.RDBMS is set to 10.1, the file size limits are less. For example, with COMPATIBLE.RDBMS equal to 10.1 and the AU size equal to 1 MB, Oracle ASM file size limits are:

External redundancy: 35 TB

Normal redundancy: 5.8 TB

High redundancy: 3.9 TB

Note:

Oracle Database supports data file sizes up to 128 TB depending on the file system. In addition, Oracle Database has a file size limit that is dependent on the DB_BLOCK_SIZE initialization parameter.